Inkjet Recording Apparatus

ABSTRACT

A controller of an inkjet recording apparatus executes, after receiving a recording instruction, first flushing by controlling a recording head to idly eject ink toward a cap from which the ink is discharged by a pump to a detachable waste ink tank. After executing the first flushing, the controller executes image recording by controlling a conveying unit and a recording head to repeat a unit action in which the recording head ejects ink onto a recording medium conveyed by a predetermined line feed length in a conveying direction. After detecting arrival of a flushing timing during the image recording both when a threshold time elapses and when one of repeated unit actions is completed, the controller executes second flushing by controlling the recording head to idly eject ink toward a fixed ink receiving member.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Japanese Patent Application No.2013-201272, filed on Sep. 27, 2013, which is incorporated herein byreference in its entirety.

TECHNICAL FIELD

Aspects disclosed herein relate to an inkjet recording apparatuscomprising a maintenance mechanism which includes a replaceable wasteink storage.

BACKGROUND

A known inkjet recording apparatuses comprises a maintenance mechanismdisposed at one end of a carriage moving area, and a flushing traydisposed at the other end of the carriage moving area. The maintenancemechanism comprises a cap for covering a nozzle surface of the recordinghead, a waste ink tank, and a pump for discharging ink sucked from therecording head via the cap to the waste ink tank.

SUMMARY

Aspects of the disclosure provide for an inkjet recording apparatus thatis configured to perform flushing to cause a recording head to idlyeject ink in a manner that may prevent a reduction of service life ofthe inkjet recording apparatus.

According to one or more aspects of the disclosure, an inkjet recordingapparatus may comprise a conveying unit configured to convey a recordingmedium in a conveying direction; a carriage configured to move in a mainscanning direction perpendicular to the conveying direction; a recordinghead mounted on the carriage and configured to face the recording mediumconveyed in a recording area by the conveying unit and to eject ink; amaintenance mechanism; an ink receiving member; and a controller. Themaintenance mechanism comprises a cap disposed in a first outside areawhich is outside of the recording area in the main scanning direction, awaste ink storage detachably attached to the inkjet recording apparatus,and a pump configured to discharge ink in the cap to the waste inkstorage. The ink receiving member is fixedly attached, in a secondoutside area, to the inkjet recording apparatus. The second outside areais outside of the recording area in the main scanning direction andopposite to the first outside area relative to the recording area. Thecontroller is configured to receive a recording instruction forrecording an image on the recording medium; execute, after receiving therecording instruction, first flushing by controlling the recording headto idly eject ink toward the cap; execute, after executing the firstflushing, image recording by controlling the conveying unit and therecording head to repeat a unit action in which the recording headejects ink onto the recording medium conveyed by a predetermined linefeed length in the conveying direction; detect arrival of one or moreflushing timings; and execute, after detecting the arrival of a flushingtiming, second flushing by controlling the recording head to idly ejectink toward the ink receiving member. Each flushing timing arrives duringthe image recording both when a threshold time elapses and when one ofrepeated unit actions is completed.

DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure, needssatisfied thereby, and the objects, features, and advantages thereof,reference now is made to the following descriptions taken in connectionwith the accompanying drawings.

FIG. 1 is a perspective view depicting an appearance of a multifunctiondevice in an illustrative embodiment according to one or more aspects ofthe disclosure.

FIG. 2 is a vertical schematic sectional view depicting an internalstructure of a printer unit of the multifunction device in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 3A is a plan view depicting a carriage and guide rails in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 3B is a perspective view depicting the printer unit in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 4A is a sectional view depicting a maintenance mechanism, whereinthe carriage is located at a position A in the illustrative embodimentaccording to one or more aspects of the disclosure.

FIG. 4B is a sectional view depicting the maintenance mechanism, whereinthe carriage is located at a position B in the illustrative embodimentaccording to one or more aspects of the disclosure.

FIG. 5 is a schematic diagram depicting the maintenance mechanism in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 6A is a bottom view depicting a port switching mechanism, in whicha suction port is in communication with a black ink port in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 6B is a bottom plan view depicting the port switching mechanism, inwhich the suction port is in communication with a color ink port in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 6C is a bottom plan view depicting the port switching mechanism, inwhich the suction port is in communication with the black ink port, thecolor ink port, and an atmosphere port in the illustrative embodimentaccording to one or more aspects of the disclosure.

FIG. 6D is a bottom plan view depicting the port switching mechanism,wherein the suction port is in communication with the black ink port,the color ink port, and the atmosphere port in the illustrativeembodiment according to one or more aspects of the disclosure.

FIG. 7 is a perspective view depicting a waste ink tank in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 8 is a block diagram depicting the printer unit in the illustrativeembodiment according to one or more aspects of the disclosure.

FIG. 9 is a flowchart depicting image recording processing in theillustrative embodiment according to one or more aspects of thedisclosure.

FIG. 10 is a flowchart depicting maintenance processing in theillustrative embodiment according to one or more aspects of thedisclosure.

DETAILED DESCRIPTION

An illustrative embodiment according to one or more aspects will bedescribed below with reference to the accompanying drawings. Theillustrative embodiment described below is merely an example. Variouschanges, arrangements and modifications may be applied therein withoutdeparting from the spirit and scope of the disclosure. In thedescription below, a top-bottom direction 7 is defined with reference toan orientation of a multifunction device 10 that is disposed in anorientation in which it is intended to be used (e.g., an orientationdepicted in FIG. 1). A side of the multifunction device 10, in which anopening 13 is defined, is defined as the front of the multifunctiondevice 10. A front-rear direction 8 is defined with reference to thefront of the multifunction device 10. A right-left direction 9 isdefined with respect to the multifunction device 10 as viewed from itsfront.

[Overall Configuration of Multifunction Device 10]

As depicted in FIG. 1, the multifunction device 10 has a substantiallyrectangular parallelepiped shape. The multifunction device 10 includes aprinter unit 11 disposed at its lower portion, a display 14, and anoperation unit 17. The printer unit 11 is configured to record one ormore images onto one or more sheets 12 (see FIG. 2) using an inkjetrecording method. As depicted in FIG. 2, the printer unit 11 includes afeed unit 15, a feed tray 20, a discharge tray 21, a conveyor rollerpair 54, a recording unit 24, a discharge roller pair 55, and a platen42. Components of the printer unit 11 are supported by a frame 68depicted in FIG. 3B. The multifunction device 10 has various functions,e.g., a facsimile function and a printing function. The multifunctiondevice 10 is an example of an inkjet recording apparatus. The conveyorroller pair 54 and the discharge roller pair 55 are an example of aconveying unit.

[Feed Tray 20 and Discharge Tray 21]

As depicted in FIG. 1, the feed tray 20 is insertable into and removablefrom the printer unit 11 in the front-rear direction 8 via the opening13 defined in the front of the printer unit 11. The feed tray 20 isconfigured to hold sheets 12 to be fed by the feed unit 15 to aconveying path 65. The discharge tray 21 is disposed above the feed tray20 and configured to receive the sheets 12 discharged, via the opening13, by the discharge roller pair 55.

[Feed Unit 15]

As depicted in FIG. 2, the feed unit 15 includes a feed roller 25, afeed arm 26, and a shaft 27. The feed roller 25 is rotatably supportedat a distal end portion of the feed arm 26. When the conveyor motor 101(See FIG. 8) is driven to rotate reversely, the feed roller 25 rotatesforward, i.e., in a direction to feed the sheet 12 in the conveyingdirection 16. The feed arm 26 is pivotably supported by the shaft 27.The shaft 27 is supported by the frame 68 of the printer unit 11. Thefeed arm 26 is urged to pivot toward the feed tray 20 by its own weightand/or by an elastic force of, for example, a spring.

[Conveying Path 65]

As depicted in FIG. 2, a portion of the conveying path 65 is defined byan outer guide member 18 and an inner guide member 19 spaced apart fromeach other at a predetermined distance in the printer unit 11. Theconveying path 65 extends from a rear end of the feed tray 20 toward therear of the printer unit 11. The conveying path 65 extends upwardly in aU-shaped manner toward the front to the discharge tray 21 via therecording unit 24. The conveying direction 16 of the sheet 12 along theconveying path 65 is indicated by a dotted-and-dashed line in FIG. 2.

[Conveyor Roller Pair 54]

As depicted in FIG. 2, the conveyor roller pair 54 is upstream of therecording unit 24 in the conveying direction 16. The conveyor rollerpair 54 includes a conveyor roller 60 and a pinch roller 61 which areopposite to each other. When the conveyor motor 102 is driven forward,the conveyor roller 60 rotate forward. The pinch roller 61 rotatesfollowing the rotation of the conveyor roller 60. The conveyor roller 60and the pinch roller 61 pinch the sheet 12 therebetween and convey thesheet 12 in the conveying direction 16.

[Discharge Roller Pair 55]

The discharge roller pair 55 is disposed downstream of the recordingunit 24 in the conveying direction 16. The discharge roller pair 55includes a discharge roller 62 and a spur 63 which are opposite to eachother. When the conveyor motor 102 is driven to rotate forward, thedischarge roller 62 rotates forward. The spur 63 rotates following therotation of the discharge roller 62. The discharge roller 62 and thespur 63 pinch the sheet 12 therebetween and convey the sheet 12 in theconveying direction 16.

[Platen 42]

As depicted in FIGS. 2 and 3A, the platen 42 is disposed between theconveyor roller pair 54 and the discharge roller pair 55 in theconveying direction 16.

The platen 42 is disposed opposite to the recording unit 24 in thetop-bottom direction 7.

The platen 42 is configured to support from below the sheet 12 beingconveyed by the conveyor roller pair 54.

[Recording Unit 24]

As depicted in FIG. 2, the recording unit 24 is disposed between theconveyor roller pair 54 and the discharge roller pair 55 in theconveying direction 16. The recording unit 24 includes a carriage 23, arecording head 39, and an encoder sensor 38A. As depicted in FIG. 3A,ink tubes 32 and a flexible flat cable 33 extend from the carriage 23.The ink tubes 32 are configured to supply ink stored in respective inkcartridges to the recording head 39. The flexible flat cable 33 connectsa circuit board including a controller 130 to the recording head 39.

As depicted in FIG. 3A, the carriage 23 is supported by guide rails 43and 44. The guide rails 43 and 44 are spaced apart from each other inthe front-rear direction 8 and extend respectively in the right-leftdirection 9. As depicted in FIG. 3B, the guide rails 43 and 44 aresupported by the frame 68 of the printer unit 11. The carriage 23 isconnected with a known belt mechanism disposed at the guide rail 44. Thebelt mechanism includes a drive pulley 47, a following pulley 48, and anendless belt 49. The drive pulley 47 is disposed at a right end portionof the guide rail 44 in the right-left direction 9. The following pulley48 is disposed at a left end portion of the guide rail 44 in theright-left direction 9. The belt 49 is wound between the drive pulley 47and the following pulley 48. The belt 49 is connected with a bottom ofthe carriage 23. The drive pulley 47 is driven, by the carriage motor103, to rotate and circulate the belt 49, whereby the carriage 23reciprocates in a main scanning direction which is along the right-leftdirection 9.

As depicted in FIG. 2, the recording head 39 is mounted on the carriage23. The recording head 39 has a plurality of nozzles 40 in its bottomsurface. The recording head 39 is configured to eject minuscule dropletsof ink from appropriate ones of the nozzles 40. While the carriage 23reciprocates, the recording head 39 ejects ink droplets toward the sheet12 supported by the platen 42, thereby recording an image on the sheet12.

An encoder strip 38B is disposed on the guide rail 44. The encoder strip38B extends in the right-left direction 9. The encoder sensor 38A isdisposed on a bottom surface of the carriage 23. The encoder sensor 38Aand the encoder strip 38B are disposed opposite to each other in thetop-bottom direction 7. While the carriage 23 reciprocates, the encodersensor 38A reads the encoder strip 38B to generate pulse signals andoutputs the generated pulse signals to the controller 130. The encodersensor 38A and the encoder strip 38B constitute a carriage sensor 38depicted in FIG. 8.

[Maintenance Mechanism 70]

The multifunction device 10 further includes a maintenance mechanism 70depicted in FIGS. 4 and 5. As depicted in FIG. 3A, the maintenancemechanism 70 is disposed to the right of the area in which the carriage23 reciprocates during image recording (hereinafter, referred to as arecording area″). The recording area is an area in which the recordinghead 39 faces the sheet 12 on the platen 42. When the carriage 23 islocated to the right of the recording area, the maintenance mechanism 70perform purging by sucking ink from the nozzles 40 to eliminate airbubbles or foreign objects together with ink. The maintenance mechanism70 includes a cap 71, a lifting mechanism 73, a pump 76 (see FIGS. 5 and8), and a port switching mechanism 90. A waste ink tank 110 (see FIGS.3B and 5) is configured to store ink sucked and removed by themaintenance mechanism 70. The waste ink tank 110 is an example of awaste ink storage. The area to the right of the recording area is anexample of a first outside area which is outside of the recording areain the main scanning direction.

The cap 71 is made of, for example, rubber. The cap 71 is disposed suchthat the cap 71 faces the carriage 23 when the carriage 23 is located tothe right of the recording area. The cap 71 is configured to movebetween a capping position in which the cap 71 covers a nozzle surfaceand an uncapping position in which the cap 71 is separated from thenozzle surface. The nozzle surface is a surface of the recording head 39in which the nozzles 40 are formed. Inside of the cap 71 is divided intotwo spaces, that is, the cap 71 includes a black-ink cap portion and acolor-ink cap portion. The black-ink cap portion is configured to covera portion of the nozzle surface in which nozzles 40 for ejecting blackink are formed while creating an enclosed space between the portion ofthe nozzle surface and the black-ink cap portion. The color-ink capportion is configured to cover another portion of the nozzle surface inwhich nozzles 40 for ejecting color (cyan, magenta, and yellow) ink areformed while creating an enclosed space between the portion of thenozzle surface and the color-ink cap portion. The black-ink cap portionis connected to a black ink port 95 and the color-ink cap portion isconnected to a color ink port 96.

The pump 76 is, for example, a rotary tube pump. When the conveyor motor102 is driven to rotate forward, the pump 76 is driven to generate aflow of fluid (e.g., ink or air) from an inlet 76A toward an outlet 76B(see FIG. 5). The port switching mechanism 90 is connected to an end ofa tube 91A extending from the inlet 76A. The cap 71 is connected to anend of a tube 91B extending from the port switching mechanism 90. Thatis, the cap 71 and the inlet 76A are in communication with each othervia the tubes 91A and 91B and the port switching mechanism 90. The wasteink tank 110 is detachably attached to an end of a tube 91C extendingfrom the outlet 76B.

As depicted in FIG. 4, the lifting mechanism 73 includes a link 74. Byrotation of the link 74 in response to the movement of the carriage 23,a holder 75 moves between a position of FIG. 4A and a position of FIG.4B. The holder 75 supports a contact lever 176 that protrudes upward inthe vertical direction. The contact lever 176 extends to thereciprocation area of the carriage 23. The lifting mechanism 73 isconfigured to move the cap 71 in response to the pressing of the contactlever 176 by the carriage 23. When the carriage 23 is not in contactwith the contact lever 176, the cap 71 is separated from the nozzlesurface. When the carriage 23 moves rightward from a position A shown inFIG. 3A and contacts the contact lever 176, the lifting mechanism 73moves the cap 71 toward a position proximate to the nozzle surface.

A wiper blade 78 is disposed in a wiper holder 77 so as to extend fromand retract to the wiper holder 78. The wiper blade 78 is configured tomove between a contact position in which the wiper blade 78 extends fromthe wiper holder 77 and contacts the nozzle surface and a separatedposition in which the wiper blade 78 retracts to the wiper holder 77 andis separated from the nozzle surface. The wiper blade 78 in the contactposition wipes ink adhered to the nozzle surface when the carriage 23slides. When the conveyor motor 102 is driven to rotate reversely, thewiper blade 78 extends from and retracts to the wiper holder 77.

[Port Switching Mechanism 90]

The port switching mechanism 90 is configured to change thecommunication state between the cap 71 and the pump 76, and to move thecap 71 toward and away from the nozzle surface. As depicted in FIG. 6,the port switching mechanism 90 includes a cylinder 99 having a bottomend and a cylindrical rotary body 92 that is disposed inside thecylinder 99. The cylinder 99 includes a suction port 93, a black inkport 95, a color ink port 96, and atmosphere ports 97 and 98.

The suction port 93 is formed in a bottom wall of the cylinder 99. Theother four ports 95-98 are formed circumferentially at predeterminedintervals in a side wall of the cylinder 99. The black ink port 95 is incommunication with the internal space of the black-ink cap portion viathe tube 91B. The color ink port 96 is in communication with thecolor-ink cap portion via the tube 91B. The atmosphere ports 97 and 98are open to the atmosphere. One end of the tube 91A is connected to thesuction port 93 and the other end of the tube 91A is connected to theinlet 76A of the pump 76.

When the conveyor motor 102 is driven to rotate reversely, the rotarybody 92 rotates (e.g., counterclockwise in FIG. 6) in the cylinder 99.The communication states of the ports 95-98 in the cylinder are changedin accordance with the rotation of the rotary body 92 in the cylinder99. In FIG. 6A, the suction port 93 is in communication with the blackink port 95. In FIG. 6B, the suction port 93 is in communication withthe color ink port 96. In FIG. 6C, the suction port 93 is incommunication with the black ink port 95, the color ink port 96, and theatmosphere port 97. In FIG. 6D, the suction port 93 is in communicationwith the black ink port 95, the color ink port 96, and the atmosphereport 98.

The cap 71 and the wiper blade 78 moves in response to the rotation ofthe rotary body 92. More specifically, the cap 71, which is moved by thelifting mechanism 73 to the position proximate to the nozzle surface, isin the capping position in the states depicted in FIGS. 6A-6C and is inthe uncapping position in the state depicted in FIG. 6D. The wiper blade78 is in the separated position at least in the sates depicted in FIG.6(D). In short, the cap 71 and the wiper blade 78 are driven to move bythe conveyor motor 102 rotating reversely.

When the rotary body 92 rotates to the state depicted in FIG. 6A, theblack-ink cap portion of the cap 71 and the pump 76 come intocommunication with each other. When the pump 76 is driven, under thiscondition, by the conveyor motor 102 driven to rotate forward, thepressure in the internal space of the black-ink cap portion becomeslower than atmospheric pressure, whereby black ink and air existing inthe nozzles 40 for black ink covered with the black-ink cap portion, orforeign objects adhering to the nozzle surface of the nozzles 40 forblack ink are discharged into the black-ink cap portion (such ink, air,and foreign objects will be referred to as ink or the like,hereinafter). Subsequently, when the rotary body 92 rotates from thestate depicted in FIG. 6A to the state depicted in FIG. 6B, thecolor-ink cap portion of the cap 71 comes into communication with thepump 76. When the pump 76 is driven under this condition, the pressurein the internal space of the color-ink cap portion becomes lower thanatmospheric pressure, whereby ink and the like in the nozzles 40 forcolor ink covered with the color-ink cap portion are discharged into thecolor-ink cap portion.

When the rotary body 92 rotates from the state depicted in FIG. 6B tothe state depicted in FIG. 6C, the suction port 93 comes intocommunication with the black ink port 95, the color ink port 96, and theatmosphere port 97 while the cap 71 is in close contact with the nozzlesurface. When the pump 76 is driven under this condition, the ink andthe like stored in the cap 71 are discharged to the waste ink tank 110via the tubes 91A-91C, the port switching mechanism 90, and the pump 76.As the rotary body 92 further rotates from the state depicted in FIG. 6Cto the state depicted in FIG. 6D, the suction port 93 comes intocommunication with the black ink port 95, the color ink port 96, and theatmosphere port 98 while the cap 71 is separated from the nozzlesurface. When the pump 76 is driven under this condition, the ink or thelike stored in the cap 71 is discharged to the waste ink tank 110 viathe tubes 91A-91C, the port switching mechanism 90, and the pump 76.

[Waste Ink Tank 110]

As depicted in FIG. 7, the waste ink tank 110 has a substantiallyT-shaped box shape in plan view. The waste ink tank 110 includes an inkabsorber 115 therein. The shape and placement of the waste ink tank 110are not limited to the above example. In other embodiments, for example,the waste ink tank 110 may have any shape that is capable of holding theink absorber 115 therein and the waste ink tank 110 may be disposed atany position inside of the multifunction device 10. In the illustrativeembodiment, the waste ink tank 110 is detachably supported by the frame68.

The tube 91C (see FIG. 5) is detachably connected to connectors 118disposed on an outer face of a rear portion of the waste ink tank 110.Ink flowing into the waste ink tank 110 from the tube 91C via theconnectors 118 is absorbed by the ink absorber 115, diffuses along aflow path indicated by a dashed line with an arrow in FIG. 7, andreaches a front portion of the waste ink tank 110. A pair of protrusions119 project in the right-left direction 9 from a lower rear portion ofthe waste ink tank 110 so as to be inserted into holes formed in theframe 68 of the printer unit 11. The waste ink tank 110 is supported bythe frame 68 via the protrusions fitted into the holes. A detectionelectrode 120 is disposed at a front end portion of the waste ink tank110.

The detection electrode 120 outputs a detection signal to a controller130 depending on the amount of ink stored in the waste ink tank 110.

[Waste Ink Tray 50]

As depicted in FIG. 3A, the multifunction device 10 includes a waste inktray 50 disposed in an area to the left of the recording area in theright-left direction 9.

In the illustrative embodiment, the waste ink tray 50 is fixed to theframe 68. An ink absorber is accommodated in an internal space of thewaste ink tray 50. The waste ink tray 50 has, at its upper face, anopening 51 which faces the lower face of the recording head 39 andthrough which the waste ink tray 50 receives ink droplets ejected fromthe recording head 30. The waste ink tray 50 is an example of an inkreceiving member. The area to the left of the recording area is anexample of a second outside area which is outside of the recording areain the main scanning direction and opposite to the first outside arearelative to the recording area.

[Driving Force Transmission Mechanism 104]

A driving force transmission mechanism 104 depicted in FIG. 8 isconfigured to transmit a driving force of the conveyor motor 102 to thefeed roller 25 and the maintenance mechanism 70. The driving forcetransmission mechanism 104 includes a combination of some or all ofgears, pulleys, an annular belt, a planet gear mechanism (e.g., apendulum gear mechanism), and a one-way clutch. Whether the drivingforce of the conveyor motor 102 is transmitted to the feed roller 25 orthe maintenance mechanism 70 is changed by the carriage 23. The conveyorroller 60 and the discharge roller 62 rotate forward when the conveyormotor 102 is driven to rotate forward, irrespective of the position ofthe carriage 23.

More specifically, when the carriage 23 is located to the left of theposition A in FIG. 3, the driving force transmission mechanism 104transmits a driving force of the conveyor motor 102 to the feed roller25, the conveyor roller 60, and the discharge roller 62 but not to themaintenance mechanism 70. In this state, a driving force of the conveyormotor 102 rotating forward is not transmitted to the feed roller 25, andthe feed roller 25 rotates forward when the conveyor motor 102 is drivento rotate reversely.

When the carriage 23 is located to the right of the position A of FIG. 3(i.e., when the contact lever 176 has been moved to the right), thedriving force transmission mechanism 104 transmits a driving force ofthe conveyor motor 102 to the maintenance mechanism 70 but not to thefeed roller 25. In this state, the driving force transmission mechanism104 transmits a driving force of the conveyor motor 102 rotating forwardto the pump 76, and transmits a driving force of the conveyor motor 102rotating reversely to the port switching mechanism 90.

A one-way clutch disposed in a transmission path defined between theconveyor motor 102 and the components allows selective transmission of adriving force of the conveyor motor 102 to the feed roller 25, the pump76, and to the port switching mechanism 90. A pendulum gear mechanism ora solenoid clutch mechanism may be used instead of the one-way clutch.The driving force transmission mechanism 104 is an example of aswitching mechanism.

[Controller 130]

As depicted in FIG. 8, the controller 130 includes a central processingunit (“CPU”) 131, a read-only memory (“ROM”) 132, a random-access memory(“RAM”) 133, an electrically erasable programmable read only memory(“EEPROM”) 134, and an application-specific integrated circuit (“ASIC”)135 that are connected with each other via an internal bus 137. The ROM132 stores programs for the CPU 131 to control various operations. TheRAM 133 is employed as a storage area for temporarily storing data orsignals to be used for the CPU 131 to execute the programs, or as aworkspace for data processing by the CPU 131. The EEPROM 134 isconfigured to store settings and flags that need to be held after themultifunction device 10 is powered off.

The ASIC 135 is connected with the conveyor motor 102 and the carriagemotor 103. The ASIC 135 receives a drive signal for rotating apredetermined motor from the CPU 131 to output a drive currentresponsive to the drive signal to the predetermined motor. Thepredetermined motor thus rotates by the application of the drive currentfrom the ASIC 135. For example, the controller 130 drives the rollers orthe maintenance mechanism 70 by controlling driving of the conveyormotor 102. The controller 130 controls the recording head 39 to ejectink from appropriate one or more of the nozzles 40. A carriage sensor 38is connected to the ASIC 135. The controller 130 detects the position ofthe carriage 23 based on pulse signals outputted from the carriagesensor 38.

The controller 130 reciprocates the carriage 23 by controlling drivingof the carriage motor 103. More specifically, the controller 130 movesthe carriage 23 at a first speed in the recording area, and at a secondspeed in an outside area which is to the right of the recording area. Inthe outside area, the carriage 23 is contactable with the maintenancemechanism 70, or more specifically, the carriage 23 contacts the contactlever 176 and moves the lifting mechanism 73. The second speed is lowerthan the second speed. This may prevent breakage of ink meniscuses inthe nozzles 39 while preventing a reduction of the throughput ofrecording processing, as will be described later.

[Image Recording Processing]

Image recording processing will be described referring to FIG. 9. Thisprocessing is executed by the CPU 131 of the controller 130. Processingsteps described below may be executed by the CPU 131 that reads aprogram stored in the ROM 132 or may be executed by a hardware circuitinstalled on the controller 130. The image recording processing will bedescribed with reference to rotations of the feed roller 25, theconveyor roller 60, and the discharge roller 62, movement of thecarriage 23, and driving of the maintenance mechanism 70. Operations ofthe rollers 25, 60, and 62, the carriage 23, and the maintenancemechanism 70 are realized by driving the conveyor motor 102 and thecarriage motor 103, as described above.

The controller 130 executes the image recording processing depicted inFIG. 9 on condition that the controller 130 receives a recordinginstruction from a user. The controller 130 may receive a recordinginstruction inputted through the operation unit 17 of the multifunctiondevice 10 or through an external device connected to the multifunctiondevice 10 via a communication network. The controller 130 control therollers 25, 60, and 62, the carriage 23, and the recording head 39 andexecutes image recording on the sheet 12. In the illustrativeembodiment, when the multifunction device 10 is on standby for receivinga recording instruction, the carriage 23 is kept at the position B andthe port switching mechanism 90 is kept in the state depicted in FIG.6C. Accordingly, the cap 71 is kept in the capping position, therebypreventing ink in the nozzles 40 from drying.

First, the controller 130 executes first flushing by controlling therecording head 39 to idly eject ink toward the cap 71 (e.g., step S11).More specifically, the controller 130 rotates the rotary body 92 suchthat the port switching mechanism 90 is brought into the state depictedin FIG. 6D while the carriage 23 remains at the position B.Subsequently, the controller 130 controls the recording head 39 to idlyeject ink while the carriage 23 is kept at the position B. The ink isdischarged from the recording head 39 into the cap 71. Subsequently, thecontroller 130 executes idle suction in which the ink in the cap 71 isdischarged to the waste ink tank 110 (e.g., step S12). Morespecifically, the controller 130 drives the pump 76 while the carriage23 and the port switching mechanism 90 are in the same position/state asthose at the time of the first flushing (step S11).

Subsequently, the controller 130 rotates the feed roller 25 forward tofeed the sheet 12 to the conveyor roller pair 54 (e.g., step S13). Whenthe sheet 12 reaches the conveyor roller pair 54, the controller 130controls the conveyor roller 60 and the discharge roller 62 (hereinafterreferred to as a “conveying unit”) to convey the sheet 12 by apredetermined line feed length in the conveying direction 16, andcontrols the recording unit 24 to record an image on the sheet 12 (e.g.,step S14). In short, the controller 130 executes the recordingprocessing after a recording instruction is received and the firstflushing (step S11) and the idle suction (step S12) are executed. StepS14 is an example of a unit action and is repeated until image recordingon the sheet 12 is completed (e.g., Yes in step S15).

On condition that one of repetitive unit actions (step S14) is completed(e.g., No in step S15) and a threshold time has elapsed (e.g., Yes instep S16), the controller 130 executes the first flushing (e.g., stepS18) or second flushing (e.g., step S19). Step S16 is an example of astep for detecting arrival of one or more flushing timings. Eachflushing timing arrives both when a time elapsing from execution of thelatest flushing (S11 or S18 or S19) exceeds the threshold time and whenone of repetitive unit actions (S14) is completed.

When the controller 130 detects one or more flushing timings in a singleimage recording processing, the controller 130 executes the firstflushing (e.g., step S18) for the first to Nth flushing timings (e.g.,Yes in step S17) and executes the second flushing (e.g., step S19) forthe (N+1)th and later flushing timings (e.g., step S19). The firstflushing in step S 11 and the first flushing in step S18 are executed inthe same manner. In contrast, in the second flushing (e.g., step S19),the controller 130 controls the recording head 39 to idly eject inktoward the opening 51 of the waste ink tray 50. More specifically, thecontroller 130 moves the carriage 23 to a position opposing the opening51 and controls the recording head 39 to idly eject ink. The ink isdischarged from the recording head 39 to the waste ink tray 50. N is anexample of a threshold number of times and is an integer greater than 0(zero).

Subsequently, on condition that image recording on the sheet 12 iscompleted (e.g., Yes in step S15), the controller 130 executesdischarging of the sheet 12 to the discharge tray 21 (e.g., step S20).More specifically, the controller 130 rotates the conveying unit forwarduntil a trailing edge of the sheet 12 (an upstream edge of the sheet 12in the conveying direction 16) passes the discharge roller pair 55. Thecontroller 130 execute steps S13-S21 repeatedly until the imagerecording on one or more pages is completed (e.g., No in step S21) asinstructed by the recording instruction.

Subsequently, on condition that the first flushing has been executed instep S18 (e.g., Yes in step S22), the controller 130 executes idlesuction (e.g., step S23) following the completion of all the imagerecording (e.g., No in step S21) and ends the image recordingprocessing. Contrarily, on condition that the first flushing has notbeen executed in step S18 (e.g., No in step S22), the controller 130skips step S23. The idle suction in step S12 and the idle suction instep S23 are executed in the same manner.

[Maintenance Processing]

Maintenance processing will now be described referring to FIG. 10. Thisprocessing is executed by the CPU 131 of the controller 130. Processingsteps described below may be executed by the CPU 131 that reads aprogram stored in the ROM 132 or may be executed by a hardware circuitinstalled on the controller 130.

The maintenance processing is executed to maintain the nozzles 40 of therecording head 39 when a predetermined time has elapsed since executionof the latest maintenance or when the controller 130 receives amaintenance instruction inputted by a user through the operation unit17. The maintenance processing will be described with reference tomovement of the carriage 23 and driving of the maintenance mechanism 70.Operations of the carriage 23 and the maintenance mechanism 70 arerealized by driving the conveyor motor 102 and the carriage motor 103,as described above.

First, the controller 130 executes purging by driving the pump 76 todischarge ink from the nozzles 40 (e.g., step S31). More specifically,the controller 130 moves the carriage 23 to the position B, rotates therotary body 92 such that the port switching mechanism 90 is brought intothe state depicted in FIG. 6A, and drives the pump 76. Black ink, colorink and the like in the nozzles 40 are sucked and removed by the pump 76via the cap 71.

Subsequently, the controller 130 executes capped idle suction (e.g.,step S32) and uncapped idle suction (e.g., step S33). More specifically,in the capped idle suction (e.g., step S32), the controller 130 rotatesthe rotary body 92 such that the port switching mechanism 90 changesfrom the state depicted in FIG. 6B into the state depicted in FIG. 6C,and drives the pump 76. In the uncapped idle suction (e.g., step S33),the controller 130 rotates the rotary body 92 such that the portswitching mechanism 90 changes from the state depicted in FIG. 6C intothe state depicted in FIG. 6D, and drives the pump 76. The driving speedof the pump 76 in the capped idle suction may be lower than that in theuncapped idle suction.

Subsequently, the controller 130 executes wiping in which the wiperblade 78 wipes the nozzle surface (e.g., step S34). More specifically,the controller 130 moves the carriage 23 leftward while maintaining theport switching mechanism 90 in the state depicted in FIG. 6D such thatthe wiper blade 78 makes slide contact the nozzle surface. After thecarriage 23 passes the wiper blade 78, the controller 130 moves thecarriage 23 reversely to the position B. Subsequently, the controller130 executes first flushing (e.g., step S35) and uncapped idle suction(e.g., step S36), and ends the maintenance processing. The firstflushing (e.g., step S35) is executed in the same manner as in steps S11and S18. The uncapped idle suction (e.g., step S36) is executed in thesame manner as in step S12 and S23 in FIG. 9

[Effects of Illustrative Embodiment]

According to the illustrative embodiment, in the multifunction device 1which includes the irreplaceable waste ink tray 50 and the replaceablewaste ink tank 110, the first flushing (e.g., step S11), in which arelatively large amount of ink is discharged from the nozzles 40 via thecap 71 to the replaceable waste ink tank 110, is executed prior to imagerecording, and the second flushing (e.g., step S19), in which arelatively small amount of ink is discharged at a time from the nozzles40 to the irreplaceable waste ink tray 50, is executed during imagerecording. Consequently, the ink absorber in the waste ink tray 50 maybe used frugally, thereby preventing a reduction of service life of themultifunction device 10. In the illustrative embodiment, the carriage23, when approaching the maintenance mechanism 70, is required to moveat a relatively low speed so as not to break ink meniscuses in thenozzles. Thus, execution of the second flushing during image recordingmay prevent a reduction of throughput of image recording.

The irreplaceable waste ink tray 50 means that the waste ink tray 50 isnot designed to be replaced in the multifunction device 10 by a user andthat a replacement waste ink tray 50 is not available. The replaceablewaste ink tank 110 means that the waste ink tank 110 in themultifunction device 10 is designed to be replaced by a user and areplacement waste ink tank 110 is available. Replacement of the wasteink tank 110 refers to replacement of not only the waste ink tank 110but also the ink absorber 115.

The first flushing (e.g., step S18) may be executed a predeterminednumber of times (N times in the illustrative embodiment depicted in FIG.9) during image recording. For example, the first flushing may beexecuted during image recording as many times as the discharged ink doesnot overflow the cap 71. Thus, a threshold number of times may be set inconsideration of the amount of ink discharged per single first flushingand the capacity of the cap 71. The image processing depicted in FIG. 9may be effective especially when prevention of a reduction of servicelife of the multifunction device 10 is prioritized over improvement ofthroughput of image recording.

High throughput is not required when an image having high resolution isrecoded on the sheet 12. The moving speed of the carriage 23 is usuallylowered in the case of recording a high-resolution image than in thecase of recording a low-resolution image, in order to increase thenumber of ink droplets landing on the sheet 12 per unit area and toenhance the accuracy of landing positions of ink droplets on the sheet12. In the case of recording a high-resolution image, high throughput ofimage recording may not be severely required and thus flushing timingsmay relatively increase. Execution of the first flushing for the firstto Nth flushing timings may prevent a reduction of service life of themultifunction device 10. The same may apply to the case where thecarriage 23 moves at a relatively low speed for other reasons than toperform high-resolution image recording.

Specifically, the first flushing (e.g., step S18) may be executed forthe first to Nth flushing timings when the resolution of an image beingrecorded exceeds a threshold resolution, and the second flushing (e.g.,step S19) may be executed for all the flushing timings when theresolution of an image being recoded does not exceed the thresholdresolution. Alternatively, the first flushing (e.g., step S18) may beexecuted for the first to Nth flushing timings when the moving speed ofthe carriage 23 in image recording is less than a threshold speed, andthe second flushing (e.g., step S19) may be executed for all theflushing timings when the moving speed of the carriage 23 in imagerecording is greater than or equal to the threshold speed.

Specifically, in step S17 of the image recording processing, thecontroller may be configured to determine whether an image beingrecorded has a resolution higher than a threshold resolution, inaddition to determining whether the first flushing has been executed athreshold number of times (N times). If both conditions that the formerdetermination is affirmative and the latter determination is negativeare satisfied, the controller may execute the first flushing (e.g., stepS18) for the first to Nth flushing timings. If at least one of theconditions is not satisfied, the controller may execute the secondflushing (e.g., step S19) for each of the flushing timings.

Alternatively, in step 17 of the image recording processing, thecontroller may be configured to determine whether a moving speed of thecarriage 23 in the recording area is greater than or equal to athreshold speed, in addition to determining whether the first flushinghas been executed a threshold number of times (N times). If bothconditions that the former determination is negative and the latterdetermination is negative, the controller may execute the first flushing(e.g., step S18) for the first to Nth flushing timings. If at least oneof the conditions is not satisfied, the controller may execute thesecond flushing (e.g., step S19) for each of the flushing timings.

The threshold number of times (N times) may be changed depending onwhich is prioritized between improvement of throughput of imagerecording and prevention of a reduction of service life of themultifunction device 10.

Driving the pump 76 somewhere in steps S13-S20 causes the conveyorroller pair 54 and the discharge roller pair 55 to rotate and convey thesheet 12 on which an image is being recorded. Therefore, execution ofidle suction is not allowed in steps S13-20. Executing the idle suction(e.g., steps S12 and S23) before step S13 or after step S20 allows thepump to discharge the ink in the cap to the waste ink tank 10 withoutaffecting image recording. The processes of steps S22 and S23 may beexecuted between step S20 and step S21. In this case, throughput ofimage recording may decrease but the threshold number of times N mayincrease as compared to the case depicted in FIG. 9. This case may beeffective especially when prevention of service life of themultifunction device 10 is prioritized over improvement of throughput ofimage recording.

In the illustrative embodiment, the first flushing (e.g., step S35) isexecuted following the purging (e.g., step S31). This may reduce thenumber of executions of second flushing and the amount of ink dischargedby the executions of second slushing. Consequently, a reduction ofservice life of the multifunction device 10 may be prevented. In themaintenance processing, the first flushing (e.g., step S35) and theuncapped idle suction (e.g., step S36) may be executed in parallel,thereby improving throughput of the maintenance processing. The firstflushing (e.g., step S11) and the idle suction (e.g., step S12) in FIG.9 may also be executed in parallel.

Although, in the above-described illustrative embodiment, the conveyorroller 60 and the maintenance mechanism 70 are driven by the commonconveyor motor 102, the conveyor 60 and the maintenance mechanism 70 maybe driven by separate motors.

Although, in the above-described illustrative embodiment, the sheets 12are described as recording media, cardboard, corrugated cardboard, andoptical disks, such as CD-ROMs (Compact Disc-Read Only Memories) andDVD-ROMs (Digital Versatile Disk-Read Only Memories) may be used otherthan the sheets 12.

While the disclosure has been described in detail with reference to thespecific embodiments thereof, various changes, arrangements andmodifications may be applied therein without departing from the spiritand scope of the disclosure.

What is claimed is:
 1. An inkjet recording apparatus comprising: a conveying unit configured to convey a recording medium in a conveying direction; a carriage configured to move in a main scanning direction perpendicular to the conveying direction; a recording head mounted on the carriage and configured to face the recording medium conveyed in a recording area by the conveying unit and to eject ink; a maintenance mechanism comprising: a cap disposed in a first outside area which is outside of the recording area in the main scanning direction, a waste ink storage detachably attached to the inkjet recording apparatus; and a pump configured to discharge ink in the cap to the waste ink storage; an ink receiving member fixedly attached, in a second outside area, to the inkjet recording apparatus, the second outside area being outside of the recording area in the main scanning direction and opposite to the first outside area relative to the recording area; and a controller configured to: receive a recording instruction for recording an image on the recording medium; execute, after receiving the recording instruction, first flushing by controlling the recording head to idly eject ink toward the cap; execute, after executing the first flushing, image recording by controlling the conveying unit and the recording head to repeat a unit action in which the recording head ejects ink onto the recording medium conveyed by a predetermined line feed length in the conveying direction; detect arrival of one or more flushing timings, wherein each flushing timing arrives during the image recording both when a threshold time elapses and when one of repeated unit actions is completed; and execute, after detecting the arrival of a flushing timing, second flushing by controlling the recording head to idly eject ink toward the ink receiving member.
 2. The inkjet recording apparatus according to claim 1, further comprising: a motor configured to drive the conveying unit; and a switching mechanism configured to transmit a driving force of the motor to the pump when the carriage is in the first outside area and configured not to transmit the driving force of the motor to the pump when the carriage is in the recording area, wherein the controller is configured to execute, after the first flushing executed before the image recording, idle suction by driving the pump to discharge the ink in the cap to the waste ink storage.
 3. The inkjet recording apparatus according to claim 2, wherein the carriage is configured to contact the maintenance mechanism in the first outside area, and wherein the controller is configured to move the carriage in the recording area at a first speed, and move the carriage in the first outside area at a second speed which is lower than the first speed.
 4. The inkjet recording apparatus according to claim 1, wherein the controller is configured to further execute the first flushing at first to Nth flushing timings and execute the second flushing at a flushing timing after the Nth flushing timing, N being an integer greater than zero.
 5. The inkjet recording apparatus according to claim 1, wherein the controller is configured to: further execute the first flushing at first to Nth flushing timings among the one or more flushing timings when the image being recorded has a resolution higher than a threshold resolution, N being an integer greater than zero; and execute the second flushing at each of the one or more flushing timings when the image being recorded has a resolution lower than or equal to the threshold resolution.
 6. The inkjet recording apparatus according to claim 1, wherein the controller is configured to: further execute the first flushing at first to Nth flushing timings among the one or more flushing timings when a moving speed of the carriage in the recording area is less than a threshold speed, N being an integer greater than zero, and execute the second flushing at each of the one or more flushing timings when the moving speed of the carriage in the recording area is greater than and equal to the threshold speed.
 7. The inkjet recording apparatus according to claim 2, wherein the controller is configured to further execute the idle suction after completion of the image recording instructed by the recording instruction if the first flushing is executed during the image recording.
 8. The inkjet recording apparatus according to claim 1, wherein the recording head comprises a nozzle surface in which the nozzles are formed, wherein the cap is movable between a capping position in which the cap covers the nozzle surface, and an uncapping position in which the cap is separated from the nozzle surface, and wherein the controller is configured to: execute purging by driving the pump while the cap is in the capping position, and after executing the purging, move the cap to the uncapping position and further execute the first flushing.
 9. The inkjet recording apparatus according to claim 8, wherein the controller is configured to further execute, in parallel with the first flushing, the idle suction by driving the pump while the cap is in the uncapping position.
 10. The ink jet recording apparatus according to claim 1, wherein the controller is configured to monitor the threshold time elapsing from completion of a latest one of the first flushing and the second flushing.
 11. The inkjet recording apparatus according to claim 1, further comprising: a motor configured to drive the conveying unit; and a switching mechanism configured to transmit a driving force of the motor to the pump when the carriage is in the first outside area and configured not to transmit the driving force of the motor to the pump when the carriage is in the recording area, wherein the controller is configured to execute, in parallel with the first flushing executed before the image recording, idle suction by driving the pump to discharge the ink in the cap to the waste ink storage. 